Will also need to update the error handling BPMN process so it provides correlation keys. We should add a task that will
alert you when you create a message object without setting correlation keys - as they are required per the specification.
1) Don't overwrite the message of all Workflow Task Exceptions to say "Something went wrong"
2) log errors when correlation evaluations fail (just so we are aware something isn't working correctly)
3) Dont make all evaluation fuctions require a current task context to execute -- that should be optional.
1) Type Safe checking on correlation properties (no more str())
2) A running workflows Correlations are once again at the key level.
# Backend
1) Both send and receive messages can have correlation_keys - and we compare these to each other to quickly assure a match (if they both exist - otherwise we fall back to comparing the properties on the receive to the sending messages payload)
2) Cleaned up the migrations to just one file
SpiffWorkflow -
- start_messages function should return message names, not ids.
- don't catch external thrown messages within the same workflow process
- add an expected value to the Correlation Property Model so we can use this well defined class as an external communication tool (rather than building an arbitrary dictionary)
- Added a "get_awaiting_correlations" to an event, so we can get a list of the correlation properties related to the workflows currently defined correlation values.
- workflows.waiting_events() function now returns the above awaiting correlations as the value on returned message events
Backend
- Dropping MessageModel and MessageCorrelationProperties - at least for now. We don't need them to send / receive messages though we may eventually want to track the messages and correlations defined across the system - these things (which are ever changing) should not be directly connected to the Messages which may be in flux - and the cross relationships between the tables could cause unexpected and unceissary errors. Commented out the caching logic so we can turn this back on later.
- Slight improvement to API Errors
- MessageInstances are no longer in a many-to-many relationship with Correlations - Each message instance has a unique set of message correlations specific to the instance.
- Message Instances have users, and can be linked through a "counterpart_id" so you can see what send is connected to what recieve.
- Message Correlations are connected to recieving message instances. It is not to a process instance, and not to a message model. They now include the expected value and retrieval expression required to validate an incoming message.
- A process instance is not connected to message correlations.
- Message Instances are not always tied to a process instance (for example, a Send Message from an API)
- API calls to create a message use the same logic as all other message catching code.
- Make use of the new waiting_events() method to check for any new recieve messages in the workflow (much easier than
churning through all of the tasks)
- One giant mother of a migration.
* SpiffWorkflow did not serialize correlations - so they were lost between save and retrieve.
* When comparing Correlation Property values - we are storing these values as strings in the database and can't convert them back to integers later, so I'm changing everying everywhere to compare after conversion to a string. Don't feel great about this one.
* By using an SQL Alchemy join table, there is a lot of db queries we don't need to write.
* A few handy fucntions on db models to make it easier to work with correlations.
* Updated tests because I changed some of the BPMN models we were testing against.
* Database migration to use the new constraint names with the alternate form of the join table between correlation mesages to instance messages.
* Clear out complex get_message_instance_receive how that many-to-many works.
* Create decent error messages when correlations fail
* Move correlation checks into the MessageInstance class
* The APIError could bomb out ugly if it hit a workflow exception with not Task Spec.
* Link between message instance and correlations is now a link table and many-to-many relationships as recommended by SQLAlchemy
* Use the correlation keys, not the process id when accepting api messages.
